IPv6 clears test hurdle, but more stress tests lie ahead

Something really cool happened last Wednesday, June 8: nothing out of the ordinary.

This was good news for the 430-plus providers, ISPs and enterprises participating in the Internet Society's (ISOC) World IPv6 Day, a 24-hour test in which content providers turned up access to their networks and/or websites via IPv6, the Internet addressing protocol set to gradually replace IPv4.

The goal of the test was simple: Operate IPv6 in the "real world" under controlled conditions to expose issues that might arise as the addressing protocol is increasingly adopted. For many participants the test included connecting their primary domain name servers to the IPv6 side of their dual-stacked architecture--google.com, for example.

Most users, particularly the end user, noticed nothing amiss. Requests via IPv4--still the vast majority of Internet traffic on Wednesday--were shunted over to providers' or websites' IPv4 side without incident or noticeable delay for the most part.

In fact, Wednesday was such a successful non-event that a few participants, including Google (Nasdaq: GOOG), its video subsidiary YouTube, and Facebook--among others--announced immediately afterward that they intended to continue supporting IPv6.

So where do we go from here?For many larger-scale providers, despite the event's success, World IPv6 Day didn't answer some important questions that could impact IPv6 deployment. It's important to note that the event wasn't meant to answer those questions, but organizations migrating to dual-stack architecture would do well to note them.

First off, the increased usage of IPv6 on Wednesday represented only 0.3 to 0.5 percent of total global Internet traffic. While this was double the usual volume of IPv6 traffic according to ISOC reports, it was still "pretty low" in the estimation of Qing Li, chief scientist at Blue Coat Systems. Only a few individuals accessed IPv6 networks, he said. "It was mostly enterprise customers and early adopters using a tunnel approach."

A real stress test of IPv6 networks won't take place until more consumers start moving onto the IPv6 structure. Tim Winters of the University of New Hampshire's Interoperability Laboratory concurred. "When you run out of v4 addresses that will be a (stress test). Once (IPv6) traffic gets over 1 percent that will start to be really significant," he said.

He pointed out that IPv6 traffic volume will cross the 1 percent threshold sometime in the next six months.

Major providers are working on strategies to begin migrating more users over to the IPv6 side of things, but that takes time. Jean McManus of Verizon (NYSE: VZ) said that the company trialed v6 last year and is working on a strategy to migrate FiOS and HSI customers.

Providers also need to look at a critical aspect of v6 migration: keeping the network secure. Being vigilant about security, developing a plan to write security protocols for v6, is important, Li noted. He recommended that organizations work with each other to test content delivery as well as security: "...try each others' web portals & do some penetration testing."

The next phaseFor the near future, there are no IPv6 tests planned at the scale of Wednesday's World IPv6 Day. But providers are continuing to test networks and devices internally, and vendor-neutral parties like the UNH-IOL will continue to host interoperability testing.

Where IPv6 testing is trending--planned or not--appears to be the consumer device market. In particular, CPEs (customer premises equipment), including both provider-installed and individually purchased equipment such as home routers, are getting a close look by companies like Verizon and have featured in at least two interop events at the UNH-IOL.

In any case, the optimistic consensus about World IPv6 Day is that it both publicized the existence and importance of the addressing protocol, and, thanks to participation by major Internet players like Google, Facebook and Yahoo! as well as network providers like Akamai and Limelight Networks, Hurricane Electric, Global Crossing (Nasdaq: GLBC) and others, hopefully increased the confidence of decision-makers in many organizations to go ahead with a transition to dual-stack architecture.

In the face of IPv4 address depletion, World IPv6 Day was an important and necessary boost toward greater adoption rates. Now the IPv6 ball is in the hands of individual organizations. It'll be interesting to see how they carry it forward.--Sam